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No exploitation reportedFix available

CVE-2026-42946

No exploitation reported by the sources we read.

  • Published2026-05-13
  • WeaknessCWE-789 · CWE-823

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability exists in the ngx_http_scgi_module and ngx_http_uwsgi_module modules that may result in excessive memory allocation or an over-read of data. When scgi_pass or uwsgi_pass is configured, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to read the memory of the NGINX worker process or restart it.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Timeline

dates in UTC
  1. 2026-05-1316:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 15:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-42946?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-42946?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
F5 nginx ingress controller
BranchAffectedFixed in
3.x≥ 3.5.0, ≤ 3.7.2no fix published
4.0≥ 4.0.0, ≤ 4.0.1no fix published
5.x≥ 5.0.0, ≤ 5.4.2no fix published
F5 waf
BranchAffectedFixed in
4.x≥ 4.9.0, ≤ 4.16.0no fix published
5.x≥ 5.1.0, ≤ 5.8.0no fix published
5.x≥ 5.9.0, ≤ 5.12.1no fix published
F5 dos
BranchAffectedFixed in
4.x≥ 4.3.0, ≤ 4.7.0no fix published
4.8= 4.8.0no fix published

6 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

  • CVE-2026-42946 Red Hat Product Security55 known affected

    nginx: ngx_http_scgi_module: ngx_http_uwsgi_module: information disclosure and denial of service

    nginx as a component of Red Hat Enterprise Linux 10 · nginx-all-modules as a component of Red Hat Enterprise Linux 10 · nginx-core as a component of Red Hat Enterprise Linux 10 · +52 more

Full record on NVD

Fix

  1. Workaround from the vendor Red Hat Product Security CVE-2026-42946 · 55 productsTo mitigate this flaw, ensure that the connection between NGINX and the backend SCGI/uWSGI servers is fully encrypted and authenticated, preventing the interception and manipulation of responses required to exploit this vulnerability.
  2. No fix available, says the vendor Red Hat Product Security CVE-2026-42946 · 44 productsFix deferred
  3. No fix planned, says the vendor Red Hat Product Security CVE-2026-42946 · 11 productsOut of support scope

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • CISA-ADPSSVC decisionnone2026-05-13
  • OpenCVESSVC decisionnone—
  • CNACVSS 4.08.3read 2026-10-23
  • CNACVSS 3.16.5read 2026-10-23
  • NVDCVSS 3.17.4read 2026-10-23
  • CNAweakness (CWE)CWE-789, CWE-823read 2026-10-23
  • FIRST EPSSEPSS score0.9 %2026-10-22
  • OSVaffected packages—
  • Microsoft MSRCadvisory—

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
CVSS 4.0 vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published
2026-05-13
Last Modified
2026-06-18
NVD status
Analyzed
MSRC Title
NGINX ngx_http_scgi_module and ngx_http_uwsgi_module vulnerability

Frequently asked questions

What is CVE-2026-42946?

A vulnerability exists in the ngx_http_scgi_module and ngx_http_uwsgi_module modules that may result in excessive memory allocation or an over-read of data. When scgi_pass or uwsgi_pass is configured, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to read the memory of the NGINX worker process or restart it.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Is CVE-2026-42946 actively exploited?

Active exploitation of CVE-2026-42946 has not been confirmed. Its EPSS score was 0.9% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-42946?

CVE-2026-42946 has a CVSS v3 base score of 7.4 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H.

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